NEW YORK — New insights into colchicine’s disruption of the pathway that contributes to arterial inflammation and new clinical studies of the drug could pave the way toward greater use of the anti-inflammatory drug in patients with or at risk for atherosclerotic cardiovascular disease (ASCVD), researchers said at the 4th Annual Cardiometabolic Risk in Inflammatory Conditions conference.
Colchicine was approved by the US Food and Drug Administration (FDA) in June 2023 in a once-daily 0.5-mg formulation under the brand name Lodoco to reduce the risk for major adverse cardiovascular events (MACE) in patients with established atherosclerotic disease or with multiple risk factors for CVD. The Lodoco formulation is slightly smaller than the 0.6-mg formulation that’s taken twice daily for the prophylaxis and treatment of acute gout flares.
In a presentation at the conference, Binita Shah, MD, one of the principal investigators in trials of Lodoco, explained how the inflammatory pathway contributes to atherosclerosis and provided an update on how colchicine disrupts the pathway. Dr. Shah is an associate professor of medicine at New York University in New York City and director of research at NYU Langone Health Interventional Cardiology.
“Colchicine dampens inflammatory markers on neutrophils so that they are less likely to be attracted to inflamed or injured endothelium, which would be the site of where plaque is building up or where the plaque has ruptured in the setting of a heart attack,” Shah told this news organization after her presentation.
The Inflammatory Pathway
Dr. Shah explained that normal coronary endothelium resists adhesion by circulating leukocytes, but inflamed or injured coronary endothelium attracts those neutrophils via two types of selectins: L-selectins on neutrophils and E-selectins on endothelial cells. Those neutrophils then release inflammatory cytokines including interleukin-1 beta (IL-1ß), which then triggers production of IL-6 and, subsequently, high-sensitivity C-reactive protein (hsCRP), which contributes to plaque formation, she said.
“Colchicine affects these pathways with a balance for safety and effect on clinical outcomes, particularly to reduce recurrent myocardial infarction [MI],” Dr. Shah said during her presentation.
Results from the CIRT trial demonstrated that methotrexate is ineffective in blocking the adenosine-mediated anti-inflammatory pathway, Dr. Shah said, so focusing on the IL-1ß–IL-6–hsCRP pathway, which is known to work based on the results of the CANTOS trial, could pay dividends.
“This is where colchicine can potentially play a role,” she said.
Dr. Shah cited a secondary analysis of the CANTOS trial in which the magnitude of hsCRP reduction correlated with a reduction in MI, stroke, or cardiovascular death. The secondary analysis showed that patients who received canakinumab and achieved hsCRP ≥ 2 mg/L had a nonsignificant 5% lower risk and those who reached < 2 mg/L had a statistically significant 25% lower risk than those who received placebo.
The COPE-PCI Pilot trial demonstrated the benefit of targeting the interleukin pathways, she noted.
Further clarification of the role of colchicine in managing patients with acute coronary syndrome may come from two other randomized trials now underway, Dr. Shah said: POPCORN is evaluating colchicine to reduce MACE after noncardiac surgery, and CLEAR SYNERGY is evaluating the best timing for colchicine therapy after an acute MI.
Dr. Shah presented preliminary data from her group from a neutrophil biomarker substudy of CLEAR SYNERGY that isolated neutrophils from patients who had an acute MI. “We treated them with various doses of colchicine and showed that the interaction between those treated neutrophils [and] the endothelial cells were a lot lower; they were less sticky to endothelial cells as colchicine was administered,” she said in her presentation. She added that colchicine also reduced neutrophil chemotaxis and neutrophil activation and potentially inhibited inflammasomes, decreasing IL-1ß production.
What’s more, colchicine has been shown to not affect platelets alone but rather platelets at the site of inflammation or plaque rupture, Dr. Shah added. “At currently used doses, colchicine does not inhibit platelet activity [by] itself, so we’ve never seen increased bleeding events, but it will dampen neutrophils’ ability to latch onto a platelet that could contribute to a clot,” she later told this news organization.
“There are multiple studies, both retrospective studies in gout cohorts as well as prospective studies in the cardiovascular cohort, that all show consistently one thing, which is that colchicine continues to reduce the risk of having a recurrent MI in patients who either have cardiovascular disease or are at high risk of having cardiovascular disease,” she said.
“I think that’s very helpful to know that it’s not just one study — it’s not just a fluke, potentially a play of chance — but multiple studies consistently showing the same thing: That there’s a reduced risk of acute MI.”